A commercially successful structural beam punch press system is marketed in the United States of America by Peddinghaus Corporation, 300 North Washington Avenue, Bradley, Ill. 60915 U.S.A. under the trade name "Beamline" as part of the structural steel fabrication line sold under the trade name "Fabriline." This prior art system is described on pages 10 and 11 of the catalog entitled "Peddinghaus PEDDIMAT Structural Fabrications Systems For Economical Structural Steel Fabrication" published by Peddinghaus Corporation and bearing, on the last page, the designation "683 GC5M." The punch presses of that system are illustrated in a greatly simplified manner in FIG. 1. For ease of illustration, some of the components and assemblies of the system have been omitted.
In conventional structural beam fabrication shops employing a system such as the Fabriline system discussed above, beams are typically automatically conveyed through an assembly of punch presses for punching holes in the beams. Beams that are processed in this manner have a central web and two parallel flanges--one flange at each end of the web. Such beams are typically designated as I-beams, wide flange beams, light beams, and American standard beams. When such beams are erected in structures, the ends of the beams and/or other portions of the beams are typically connected together with bolts. The bolts are received in holes provided in the webs and flanges of the beams.
One conventional method for providing the holes in a beam is to punch the holes with one or more conventional punch presses. "Web" punch presses are used to provide holes in the beam web, and "flange" punch presses are used to provide holes in the beam flanges. Such punch presses may have conventional designs well-known to those skilled in the art. Various designs are disclosed in U.S. Pat. Nos. 4,631,996, 3,722,337, and 3,720,125.
The above-referenced conventional "Fabriline" system for punching holes in the flanges of the beam is illustrated in FIG. 1 wherein a beam 20 is conveyed in a generally horizontal orientation and has a horizontal web 22, a front flange 24, and a rear flange 26.
Holes are provided in the front flange by a front flange press unit 30, and holes are provided in the rear flange by a rear flange press unit 32. These units are oppositely facing but laterally offset along the length of the beam and are generally identical. The front flange press unit 30 punches holes in the front flange from the front side of the beam 20, and the rear flange press unit 32 punches holes in the rear flange from the rear side of the beam 20. Each press unit 30 and 32 includes a pair of spaced-apart, vertically aligned punch presses, namely a hydraulic cylinder operated upper punch press 36 and a hydraulic cylinder operated lower punch press 38. The upper punch press 36 punches holes in the flange above the web 22, and a lower punch press 38 punches holes below the web 22.
Such conventional punch press systems are adapted to process a variety of different size beams. Accordingly, one or both of the units 30 and 32 is adapted to be moved toward or away from the other unit so as to accommodate narrower or wider beams, respectively. Further, the flange press units 30 and 32 are each adapted to be moved vertically so as to locate the punch presses 36 and 38 on the flanges at selected distances from the web 22.
Typically, the four punches are operated separately and not simultaneously. For example, the beam 20 may be initially positioned lengthwise for punching the rear flange 26 with the rear flange press unit 32. The rear flange press unit 32 is then moved vertically to position the upper punch press 36 on the rear flange 26 above the web 22. After the upper punch press 36 of the rear flange press unit 32 is operated to punch the hole, the unit 32 is moved vertically, if necessary, to locate the lower punch press 38 of the rear flange press unit 32 adjacent the rear flange 26 below the web 22. If the second hole to be punched is not vertically below the first hole that was punched above the web 22 in the rear flange 26, then the beam 20 is moved lengthwise as necessary, and the second hole is then punched in the rear flange 26 below the web 22.
Subsequently, the beam 20 is moved lengthwise to position the front flange for being punched by the front flange press unit 30. The front flange press unit 30 is moved vertically upwardly or downwardly as necessary for the punching of the front flange 24 by the upper and/or lower punch presses 36 and 38, and the beam at 20 is moved lengthwise as necessary for proper location relative to the upper punch press 36 and lower punch press 38.
It will be appreciated that each flange press unit 30 and 32 includes a relatively massive, unitary, inner frame 40, having a generally "C"-shape, which forms a large portion of the upper punch press 36 and which forms a large portion of the lower punch press 38. The punch presses 36 and 38 include various conventional subassemblies and components mounted to the unitary inner frame 40. The inner frame 40 itself is carried by a conventional intermediate frame 50 and includes conventional mechanisms, such as hydraulic operators 54, for moving the inner frame vertically. An outer frame 60, which includes mounting rails 62, is provided for supporting the intermediate frame 50 and for permitting the intermediate frame 50 to be moved inwardly or outwardly relative to the beam 20. Conventional mechanisms, such as connecting rods 64 and hydraulic operators (not illustrated), are employed for this purpose.
The inner frame 40 of the front flange press unit 30 and the inner frame 40 of the rear flange press unit 32 are each relatively massive. Specifically, the upper and lower portions of each frame 40 must have a sufficient mass projecting outwardly from, and around, the punch press die so as to have sufficient strength to rigidly support the die against the punching forces. This results in the upper and lower portions of the frame 40 extending outwardly a considerable distance across the width of the beam. Accordingly, as best illustrated in FIG. I, the front flange press unit 30 must be offset laterally, along the length of the beam 20, from the rear flange press unit 32 to avoid interference, at least when used to punch small (narrow) beams. If the conventional press units 30 and 32 were located on either side of the beam 20 in a direct, opposed relationship transverse to the length of the beam 20, then the units 30 and 32 could not be positioned close enough to accommodate many of the narrower structural beams. Accordingly, the front and rear flange punch press units 30 and 32 are conventionally spaced apart along the length of the beam by an amount sufficient to accommodate the dimensions of the press units along the length of the beam and by an amount sufficient to provide adequate clearance for installation, service, and maintenance.
With the conventional flange punch press configurations described above, the front flange press unit 30 and the rear flange press unit 32 are each separately movable on individual sets of tracks or rails 62 and are typically spaced apart about five feet (i.e., from the center line of one flange press unit to the center line of the other flange press unit). While such systems work well in the applications for which they were designed, it would be desirable to provide an improved system that could be operated more easily and more efficiently.
Further, it would be advantageous if such an improved system could employ an arrangement that would reduce the number of parts and components so as to provide a less costly design.
It would also be beneficial if such an improved system could be provided with a very compact arrangement that would reduce the floor space required for the system and its operation. This would permit the overall installed cost to be reduced on a shop floor space basis.
It would also be desirable to provide an improved punch press assembly for more efficiently punching holes at end connection regions in beams. With conventional systems, the rear flange punch press unit is spaced a number of feet away from the front flange punch press unit relative to the length of the beam. Thus, the end connection region of the beam (where the holes are needed for the bolted beam connection) can be located adjacent only one or the other of the punch press units. Since the upper and lower punches in a conventional unit are fixed vertically relative to each other in that unit, it is usually possible to punch only one hole at a time in the flange at the end region of the beam.
It would be desirable to provide an improved punch press arrangement wherein at least two holes could be punched simultaneously in the flanges at the end connection region of a beam.
With the conventional "Beamline" punch press system described above with reference to FIG. 1, a pair of probes 70 is provided for each of the four punch presses. (A pair of probes 70 is most clearly illustrated for the rear flange press unit 32 on the upper punch press 36.) One probe 70 of each pair is provided on the upstream side of a punch press, and the other probe of the pair is provided on the downstream of the punch press. The two probes of the pair are mounted for being vertically positioned together as a unit relative to the punch press and beam.
Each probe pair is mounted on a lead screw 72 which moves the pair of probes 70 up or down to engage the web of the structural beam. For each pair of probes 70, appropriate switches (not illustrated) are provided for being actuated when a hollow plunger 74 carried by each probe engages the beam web. For each hole that is punched in a flange by the adjacent punch press, the associated pair of probes 70 is moved vertically to engage the beam web and thus determine the web elevation. The punch press can then be positioned vertically as necessary relative to the web for punching the hole at the desired elevation in the flange.
Each punch press requires a pair of probes 70--one on each side of the punch press--so as to enable the system to punch holes close to the leading or trailing ends of the structural beam. That is, if a hole is to be punched by one of the presses very close to the leading end of the beam, then the probe mounted on the downstream side of the punch press would not be able to engage the beam web since the leading end of the beam would not project far enough downstream of the punch press to extend adjacent that downstream probe. In that case, the probe on the upstream side of the punch press would engage the beam web and actuate the switch.
Analogously, when a hole is punched close to the trailing end of the beam, the probe on the upstream side of the punch press would not be able to engage the web since the beam would not extend rearwardly far enough beyond the punch press to be adjacent the upstream probe. In that case, the probe on the downstream side of the punch press would engage the web and actuate the switch.
It would be desirable to provide an improved punch press system with an improved arrangement that would permit sensing of the web location with a reduced number of probes.
It would be desirable to also provide such an improved punch press system with an improved arrangement for controlling the positions of the punch presses in response to the sensing of the structural beam location. This would accommodate improved repetitive accuracy on hole patterns and would improve efficiency. Such improvements would have a salutary benefit of accommodating operation of the control system to minimize processing time by utilizing high operational speeds based on increased measuring accuracy.